Slashdot videos: Now with more Slashdot!

View

Discuss

Share

We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

core plexus writes "This article describes a proposal from a Japanese corporation that wants to thrust the Interior Alaska community of Galena into international limelight by donating a new, unconventional electricity-generating plant that would light and heat the Yukon River village pollution-free for 30 years. There's a catch, of course. It's a nuclear reactor. Not a huge, Three Mile Island-type power plant but a new generation of small nuclear reactor about the size of a big spruce tree. Designers say the technology is safe, simple and cheap enough to replace diesel-fired generators as the primary energy source for villages across rural Alaska."

I love it when people don't read the article. I assume this small hand grenade is one of the "bunker busting" variety? If you read the article, you'd discover that due to the design of the reactor, it is virtually impossible to make it go critical. Even if you found a way (neutron enhancement ray?), the damn thing is buried underground, where most of the shock of an explosion would be absorbed by the surrounding dirt.

Not to flame the prior poster, I just can't resist the chance to clarify some common misconceptions about nuclear reactors.
# 1 - A critical reactor is bad;
A critical reactor is a stable reactor.
K effective is the ratio of neutrons in the current generation vs neutrons in the last generation.
A critical reactor is when K effective is equal to one. That is the number of neutrons is not changing. ( that is the reactor power is stable)
A sub critical reactor is when K effective is less than one ( The r

Again, RTFA. The steam loop is secondary. The primary loop is liquid sodium and located below ground. You'd have to be one fancy driver to even hit the secondary loop, considering that it's in the middle of a concrete building, and getting to the primary loop would be nigh impossible. Furthermore, security around nuclear power plants tends to be pretty tight. When's the last time you heard of any one, anywhere in the world, getting an unauthorized pickup near a reactor building, or even onto a campus?

With a gift of essentially free energy for a couple of decades, I'm sure some of 2+ million (700000 gallons at $3+ per gallon) they spend on gas (for generators) annually could be spend bringing in security personelle.

A million plus dollars buys a security force more than able to gaurd the perimeter around a complex not larger than a school building. Security is then essentially free for these people, and in fact they are still saving a lot of money per year in energy costs. Plus they are paying for a service in their community to people that will be living in their community. And those security people will spend money somewhere.

This solution may not be fesible when there are cheaper fuel alternatives, but out there it seems to make a lot of sense.

> Ram the pipes coming out of the ground with a pickup. Let blow some steam out. Drop grenade.

Listen to grenade go *BOOM*. Realize that one needs to read up on nuclear reactors.

You really don't know the first thing about how these things work, do you? What would you possibly hope to accomplish by dropping a grenade into the secondary coolant loop, other than stopping power output, which would be accomplished by the truck hitting the pipes?

A major Japaneese corporation donates a high tech, ultraclean nuclear reactor to remote Alaskan village. The plant goes online, and everyone is happy until....

One day, all contact with the village is lost. A crack team of physicist/commandos are sent in, headed by Jean-Claude Van Damme or Vin Dielel (the Governator's too busy). What they find will SHOCK and HORRIFY the world, horribly disfigured villagers, mutant killer walruses (they came inland, they're mutants!) and a conspiracy going further than they could have imagined.

I wonder why they some small "village" in Alaska - perhaps this technology isn't as safe as they might like us to think?;)

There's actually some sound reasoning behind this. By putting such a nuclear reactor in a small village, they will be able to provide power to the entire surrounding area instead of just a fraction. If this was placed in a large city, you would have to somehow partition the power grid into small pieces. Not impossible, but not as easy as simply replacing the diesel generators at this small village.

They may also be trying to market this specifically as a solution for those small, remote sites. Imagine how much diesel fuel would be burned over the course of thirty years -- then realize that a small amount of nuclear fuel could do the same job. Yes, yes, I know that nuclear waste will last much longer than thirty years. The advantage, however, is that nuclear waste is much more manageable and, if taken care of properly, is not as damaging to the environment.

And if something goes badly wrong, is anyone really going to trek through the snow and ice to check things out? Just kidding.

While the Japanese nuclear "industry" is one of the worst in the world in terms of safety, it's impressive that reactors are this small, and maybe this will eventually come to be the standard for electricity generation in places where the other fossil-friendly alternative - namely hydroelectric power - is not an option.

WARNING: RADIOLOGICAL HAZARD. DO NOT OPEN; NO USER-SERVICEABLE PARTS INSIDE. IF DEVICE BECOMES OVERLY WARM, IMMERSE IMMEDIATELY IN HEAVY WATER AND CALL THE U.S. ENVIRONMENTAL PROTECTION AGENCY'S RADIOLOGICAL EMERGENCY RESPONSE TEAM. DO NOT USE WHILE PREGNANT OR NURSING AN INFANT. DOES NOT CONFER SUPER-POWERS UPON USER. KEEP AWAY FROM EASILY-MUTATED ARACHNIDS.

it's impressive that reactors are this smallAccoring to the headline, the reactors are about the size of a big spruce tree.Why is this impressive? US subs and aircraft carriers are powered by nuke plants which are in the same rough size, if not smaller as a spruce (which, according to this [jaredsgarden.com] pages stats are roughly in the range of 30-60 ft tall and 20-30 ft wide). And the boat and ship nuke plants have been around for many years, too.What would be impressive, though, is if they CAN indeed run trouble free fo

Its impressive b/c, unlike reactors aboard SSN/SSBN/CVNs, there won't be an ocean of water around it to pull water in from, and it won't be moving fast enough to create the convection currents that allow (at least submarine) reactors to function without pumps.

The failed reactor at Chernobyl was spilling molten fuel out of ruptured cooling bulkheads.

Nope. The Chernobyl reactor caught fire. It used a graphite moderator (a design not used in the US) which caught fire when the coolant water boiled down low enough to expose it to air. The Chernobyl design was basically an accident waiting to happen -- it was actually worse than a meltdown. (In a meltdown you're left with a pool of radioactive metal that's no longer critical all over the floor of the containment

Considering what I've seen my town waste $20 millon on, this thing seems like it could be downright affordable. How's a power hungry (I mean that in many ways) local governement to decide? More control over the local power grid (they love control) or nuclear material in town (there probably already is some, but ignorance is bliss). Such a dilema.

Reactors such as these, if they are indeed safe for residential use, would go a long way towards preventing another regional blackout (like the one we enjoyed several months ago in the US). Decentralizing the power grid has always been a challenge, and this could make it simple - if it is indeed safe.

"The word 'nuclear' makes me nervous," said Randy Virgin of the Alaska Center for the Environment. "But we've long seen the problems with diesel, and I'm pretty excited about the prospect of a clean source of energy," he said. "It sounds very promising, but I'd approach it with extreme skepticism."

There is soooo much less polution from nuclear reactors given the probability of worst case scenarios versus the diesel they are currently using. Why are we still burning fossel fuels!@!#@#!@!#

They arent in a location very suitable for wind/solar either, so nuclear seems like the best non-renewable solution.

Such a backwards society we live in, when technology is available and safe, and we delay in implementation.

Such a backwards society we live in, when technology is available and safe, and we delay in implementation.

Clearly a name change is needed. Just like MRIs (magnetic resonance imaging) used to be called NRIs
(nuclear...). Maybe something like "elemental decay engines" would be less scary for the illiterate masses?

I can hear them now: "It has the word 'decay' in it. Is it like composting?"

We're still burning fossil fuels because they're cheaper. Without regulations that force companies to pay for the pollution they generate, fossil fuels will always be cheaper than other forms of energy.

Nuclear energy is barely cost competitive now, and the only reason they are even close to competive is because of the heavy government subsidies that the industry gets. Without subsidies, nuclear energy wouldn't be cost effective at all, and the industry in every country is heavily subsidized. One of the biggest subsidies is governments acting as an insurer of last resort since regular insurance companies are not willing to offer policies against nuclear accidents.

I would rather see companies be penalized (via taxation) for the pollution they generate, which they can pass on to me in the form of higher prices, or they can switch to cleaner energy sources and offer me cheaper prices. At the same time, governments can stop subsidizing other forms of energy, which can be passed on to me in the form of lower taxes. As the markets rationalize, I suspect that I will see a net gain, while government tax income will be revenue neutral.

Sadly, this won't happen in America, since Republicans are mostly beholden to big oil, and Democrats are mostly beholden to the greens, neither of whom have my interests at heart.

Without regulations that force companies to pay for the pollution they generate, fossil fuels will always be cheaper than other forms of energy.

Those expenses are hard to enumerate. I'd go ahead and try to estimate them and apply a tax to gas accordingly, but there is another cost which is easy to enumerate. How about the cost of interventions in the Middle East? The only reason we launch cruise missles like they were practice rounds on the target range is because of the oil under the ground. If the cost of Middle East wars were tacked onto gas, you can bet that alternative energy would look more attractive.

It's a win-win too. Anti-war protesters can't complain about the wars over there if they buy gas for their car. If they want to set an example and use other sources of power, then they can rest assured they aren't spending their tax dollars on bullets. If the true cost of oil is high enough people will stop buying it, and we won't end up invading the middle east every 5-10 years. Without the huge flow of cash and the US state department pushing the status quo you can bet that democracy is a lot more likely to fluorish over there as well.

Plus, this would all be sustainable in the long run.

Let people buy oil, nuclear, or whatever. Leave it up to each individual to decide what makes the most sense. Just make sure each option is priced with all its associated costs factored in. If it costs less to clean up after one source of power, then make sure it is taxed correspondingly less.

This was already done in remote parts of Soviet Russia. The problem is that the devices went without supervision and were subsequently plundered by scrap metal thieves. See http://archives.tcm.ie/breakingnews/2001/05/24/sto ry13735.asp for an article about the problem.

The showed footage of a clean up of one of these on a documentary on terrorism - done by Frontline maybe? (definitely PBS whatever it was) They found the fuel after some woodsman came down with radiation sickness.

It took a large team of men, working in short shifts most of a day to get it in a container. It did not look like something I would want to do, even if the pay was good, though I doubt it was.

They say the Russians built quite a few of these little self-powered navigation towers.

Anyone remember that movie with David Soul (Hutch) where the Soviets invade via Alaska? Cool concept at the time. This sort of idea reminds me of the whole "Alaska is very big. Like, I mean, VERY big." concept. Even on a map, Alaska looks very big, even when taking into consideration the fact that the map is just a very small representation of something else that is much larger. Know what I mean?

Seems that our rogue, zealot enemies (no, not linux zealots) could try to do some damage/steal stuff in a remote

Except that its in a hardened, sealed concrete enclosure, meaning there would be no way to access the material short of digging it up, and then using a jackhammer and doing some welding to get inside the facility. On top of this you'd have to shut the reactor down, so you'd have an entire village that knows something is up. Add to that that this is NON-WEAPONS grade Uranium, and there is much less motivation. If a bad guy wanted just plane radioactive material there are far far far easier ways to get a hold of it, than these reactors.

I have to say after reading the article, the reactor design does sound very safe. Here is a quick rundown of reactor advancement...

-Big hunk of uranium in a pool of water*. Water heats but is under pressure so it can't boil. The water (contaminated and radioactive) is then piped through fresh water (in sealed pipes) from a lake or river transferring heat so the fresh water will boil and turn turbines. Neutron absorbing control rods are raised or lowered into the big hunk of uranium to control the reaction. Problems can occour with pipes corroding and releasing contaminated water*, control rods can jam, leaks in the coolant water* can cause a loss of coolant leading to an overheated reactor.

-Little pellets of uranium in a pool of water*. Same principle as above, only there are no control rods. As the pellets heat up, the expand, increasing the distance between the pelets. This is much safer because there are no control rods to jam. Loss of coolant can still be a problem, but easily solved by simply moving the pellets further apart.

-And now, this reactor.. a Big Rod of Uranium is immersed in a pool of water*. The rod of uranium is sub-critical so it can't sustain a (large) heat producing reaction on its own. A sleve made of neutron reflecting material (google for nuclear bomb neutron reflector) slowly makes its way along the BRoU over the reactors 30-year lifespan. Only the uranium surrounded by the sleve can react. If the sleve moves too fast, then the reactors lifespan is simply shorted - it will never produce more heat than can be made via the reflector. If it moves too slow, the reactor simply produces less heat. Overall a very good design. If I were to have a reactor in my backyard, I definately would choose this style.

I've gotta hand it to the toshiba people.. I wouldn't have thought of this... pretty cool.

*Note: Water may not be water. Water is often used because of its high specific heat, but many other liquids have been used as coolant. In the toshiba reactor, liquid sodium is spec'd because its non-corrosive. A big plus in a maintenance-free environment.

(I used to operate a nuclear reactor, so I have some idea what I'm talking about here).

I'm a bit skeptical about the reflector mechanism: certainly, it makes sense to use a neutron reflector to modulate reactor output. But the business about "if the sleeve moves too fast, then the reactor's lifespan is simply shorted" doesn't make any sense to me.

The lifetime of most reactors is determined by the buildup of "poisons" (neutron-absorbing waste products) in the fuel, which is why reprocessing plants work so well: unlike a coal plant, a nuclear plant generally doesn't get more than a small fraction of the available energy out of its fuel, so you can chemically repair the fuel and use it again.

But the buildup of poisons in the fuel is dependent on the total amount of energy released so far. So moving the reflector too fast should either (A) produce more heat or (B) not affect the lifetime of the core very much. Toshiba seems to be claiming (not-A) and (not-B), which doesn't jive (prima facie) with reactor physics.

Correct background, but incorrect conclusion. Cutting costs does not kill people, and the example does not support that premise. The example supports this conclusion: Not following the spec from the engineer kills people. Cutting costs (when within accepted engineering practices) has never hurt anyone.

Seems like you could scale the tech down even more and provide one of these bad boys for every home. So now instead of a plumber, you call some overpriced nuclear engineer (named "Buddy") and have him expose his butt crack while he works on your reactor. Of course he'll never have the "right" part with him and he'll have to fly back to Japan to pick up that spare "reflector thingy" and schedule another service call. In the mean time, the husband will come home and rig something up with cardboard and alum

Remember the 'Foundation' series? This sounds like it came straight out of there. Minature Atomic Reactors. Of course Asimov assumed that 'Atomic' was the brave new future and was envisaging reactors the size of a walnut.

This is the best idea ever. And once we have cheap, safe affordable Spacelift - that is, the ability to get into space with stuff - then all our spent fuel can easily be disposed of.

Once in orbit, you simply sypersync it toward the sun... or even better, use space elevators to directly fling the stuff to the sun. It doesn't travel thruought the cosmos to wreck someone else's problems, and there is no need to bury it in anyone's backyard. You can even use nuclear powered spacecraft to do it if you dont h

Is that they get what, about 80% of their power from Nuclear reactors? While nuclear reactors pose a risk, the overall safety of these plants has been pretty good. How many are there arcoss the world and only two major incidents?

Yes, what to do with the spent fuel is a problem, but is the cost of storing the degrading material higher than what we pump into the air each year? Let's face it Solar and wind are not there yet. (Although if your looking to make a worth while investment in your home, consider adding solar cells if you live anywhere outside of the pacific northwest, my father did and uses it to heat water and some applices and its paid for itself in 3 years. Me I still rent, so someday)

I wish people would get over their nuclear phobias and NIMBY additudes because something needs to be done, and adding more gas turbines and coal plants are not the best solution.

What's the other major accident? Everyone knows about Chernobyl, of course. And everyone talks about TMI, but the fact is that there is not a single death traceable to TMI, and there was basically no release of anything harmful.

The actual proportion in France is 75% of electric power generation from nuclear. Another 15% is other "clean" power, such as hydro. The remaining 10% is evil dirty "burning stuff" electricity. I live pretty close to about five reactors here, and I feel pretty safe. It's preferable to having a bunch of coal plants dumping crap (including a fair amount of uranium!) into the air.

Nuclear really is the way to go. The only major accident, Chernobyl, was only possible due to the collusion of a horribly unsafe plant design, and moronic operators who decided to run an experiment (i.e. try something out that was way beyond the design specs) and turn off all of the safety systems while they were doing it. So, surprise surprise, the thing made a big KABOOM.

If coal plants had to live under the same radiation emission guidelines as nuclear power, they would never be able to operate. So I agree completely, get rid of nuclear phobias (in other countries, there doesn't seem to be a lot of it here!) and get rid of heavy pollution in electrical generation.

TMI is a great advert for nuclear power! Everything that could go wrong went wrong, and the operators made mistakes. The core melted, but no-one was killed or injured.
The same can not be said about coal mining disasters, Bhopal (a chemical plant in India which exploded) or oil rig accidents. If you have a social conscience you will support nuclear power. Other energy industries regularly kill its employees and members of the public.
Alaska suffered terrible environmental damage when Exxon Valdez crashed. To prevent that happening again we need to embrace clean new clear power!

It's got a design where it needs mechanical energy to stay critical, so it can't break down and stay critical, and over-production won't increase the production rate. It doesn't irradiate the parts that could need to be serviced or any liquids. It contains the fuel needed for 30 years, which isn't that much in terms of a big plant (121 days supply for a normal-sized plant). Won't need to be changed for 30 years, and it'll be pretty obvious if someone tries to steal the core.

The only problem I can see with it (aside from public perception) is that it involves a shaft dug into permafrost. I'd be somewhat worried that a wet fall followed by a sudden cold spell could lead to the shaft getting crushed.

Of course, it will be hard to sell people on, despite the fact that this is probably a much safer thing to have in your back yard than a gas main. I'd like one in my back yard, except for the fact that it's not cost-effective to run, unless you're in the middle of nowhere in a place without sunlight.

The typical response with most nuclear devices is "not in my backyard". However, the technology used in modern reactors is exactly the type I DO want. And yes, they can put it in my backyard (heck, they can put it on my property for free, in exchange for free hydrogen, electricty, and heat). I hadn't considered Alaska as a retirement location, but where do I sign up?

I used to work at a US reactor in IT. At the time I was both amazed and stunned by the 1960's erz technology in use in the plant.

Because it had to be "certified" and documented, the cost was outrageous. Each section of pipe had to come from a certified company built by a certified company and using materials (ore, etc) from a certified place, all documented of course. Makes you feel better about the construction, but costs a lot and requires lots of maintenance.

At the time I saw some specs for a new, simple design to be used in Asia and submitted to the NRC. It used less people, more gravity fed pumps and flows, and should have lowered the cost of plants from billions to hundreds or even tens of millions.

Nothing came of it and it was a larger scale than this, but it was a good idea. Nuclear has a place when built well and conservatively, which it seems this design is.

If you think nuclear waste will need to be kept around for hundreds of thousands of years, check into actinide burners.

It looks like we may be able to break down the seriously radioactive stuff from nuclear fuel and turn it into the stuff that is only slightly radioactive (think dangerous for about 100 years.)

So we reprocess the spent fuel, which we aren't doing now. That's 90% of your mass right there that you extract and put back into the reaction.

Now take that 10% and extract the 2% plutonium that is in it and use that in one of the nuclear plant designs that can run on plutonium/uranium mix.

Now with the 8% that is left, process it in an actinide burner and you have a small amount of material that needs only to be kept for 100 years before it isn't really very radiactive. In practice, the closer you get to the 100 year mark the less dangerous it becomes.

MIT has been working on an even safer method for years: Pebble Bed reactors. The idea is: seal the uranium in bocci-ball sized graphite balls (uranium reaction won't get hot enough to melt the graphite balls). to stop the reaction roll the balls away from each other. when the fuel is spent, the U is sealed in graphite.

Also, whenever people invoke Three MIle Island, I'm always obliged to point out that ZERO nuclear waste was released during the accident. It was all completely contained. Most people think it was like Chernobyl, but the fact is: the safety standards worked for 3-mile.

For each element, there is a small list of stable isotopes. If a nucleus becomes unstable for whatever reason, it attempts to return to a stable configuration. There are several ways this can happen, including radioactive decay and fission.

The nucleus of any atom is held together by binding energy, and tries to fly apart due to electric repulsion between the protons. The binding energy per nucleon has a broad maximum around 8 MeV and nuclear mass between 50 - 75. Unstable, heavier nuclei may undergo fission into smaller nuclei with higher binding energy. The difference is released as heat, which we use to generate power.

The electric repulsion increases as the square of the number of protons in a nucleus, so more neutrons per proton are needed for heavier elements to maintain stability; however, there is a limit, and elements beyond Bismuth (83) are naturally unstable. These nuclei undergo radioactive decay, which occurs in two types: alpha and beta.

Unstable, heavy nuclei emit alpha particles, which are identical to Helium nuclei -- two protons, two neutrons. This radiation reduces the atomic mass by roughly four, eventually bringing the element to a stable nucleon count. Unstable nuclei also can undergo beta decay, converting a neutron into a proton and a high-energy electron, which is emitted. The amount of time needed for half of a sample of material to radioactively decay is called the half-life.

For fission, there are only three isotopes with a long-enough radioactive half-life to be stored and transported, and which are fissionable by neutrons of all energies: Uranium-233, Uranium-235, and Plutonium-239. U-233 isn't natural, and is created by inducing Thorium-232 to undergo beta decay by adding a neutron. U-235 occurs in small but extractable quantities in natural Uranium ore. Pu-239 is created by U-238 neutron capture and beta decay.

Alpha- and beta decay cause ionization in matter with which they come in contact by knocking off outer-shell electrons. Alpha radiation for Pu-239, the most energetic alpha decayer in a reactor at 5.1 MeV, has a range of only 3.6 cm in air, after which it is low-enough energy to absorb two electrons from the air and become a Helium atom which can't ionize. Uranium reactors, like the Toshiba model, have even smaller alpha ranges. Nuclear reactors are not at risk for leaking alpha radiation.

Beta radiation consists of electrons, which are much more likely to scatter when they ionize, so there isn't a specific ionization range for beta radiation. On the other hand, the highest energy beta radiation from fission reactions is on the order of 3 MeV, and can be stopped by half a centimeter of concrete. There is no possibility of beta radiation escaping nuclear reactors.

Gamma radiation, produced by neutron capture reactions, drops off exponentially as it is absorbed, so it can be reduced to background levels by a manageable thickness of iron or lead shielding. Normally, this occurs immediately surrounding the reactor vessel itself. If the vessel develops a leak or the shielding fails, nuclear plants have additional concrete shielding and containment procedures. In the unlikely event that everything fails, exposure to reactor gamma radiation is comparable to going to a doctor for X-rays -- not something you'd want for prolonged periods, but not going to injure you before you evacuate. In the case of the Toshiba reactor, which is 60 feet underground, there is no possibility of gamma leakage because the ground acts as shielding.

A) the "dirty bomb" (a current favorite among hte fear mongering media) made out of radioactive materials is generally NOTHING like the multiple-megaton weapons that make the big fancy mushroom clouda. These are bombs that expode conventionally, and through said explosion, scatter radioactive materials around an area, creating a hot zone that will possibly kill, probably sicken, some people right near the area, but mainly just go to scare the millions of people into knee-jerk reactions though non-understanding.

B) Making a cheap and nasty little dirty bomb can be easily done by stealing the Cesium 137 out of a few hospitals (canisters of it are used in x-ray machines - i think its an xray machine). The added benefit of this is that the material is a very fine powder that can get spread widely by the wind.

One of these canisters got loose in Brazil once. [pbs.org] Resulted in killing four and made a few people sick. THe cleanup was a tad nasty. People heard about it, and thousands of them showed up at hospitals to get checked out for possible contamination. This was after local officials told them "Look, you were in the immediate area, youre going to be fine." People still stood on line at hospitals, choking hospital resources and generally fucking up their ability to take care of those that were really hurt.

Stealing a fat hunk of reactor core would involve about a million times work, and unless they wannt rub the thing against a cheese grater for a while, they're left with one solid hunk of radioactive material, which is fairly easy to handle, contain, and bury somewhere.

[again, go read that NOVA site.]

C) Your average goober (read: 98% of the population) is completely unaware of that fact that we're constantly being bombarded with "background radiation" every second of every day. They're also unaware that our skin does a pretty good job of fending that low-level shit off.

D) Imagine if mass media existed at today's level in Edison's time. Getting people to accept the fact that electricity was not going to jump out of an unused outlet (or a wire) and kill you [in everyday non-dubmass use] would be next to impossible, and/. would have to be implemented using little peices of paper, fine point pens, and hundreds of thousands of really, really tired carrier pigeons.

E) People Die. Its something we all do, and ya can't avoid it, so stop fucking scaring yourselves into non-action. You can only hope its not going to be horrible. Generally, not being a stupidass - and keeping yourself aware of (AWARE, not SCARED) the other stupidasses around you - will go a long way in accomplishing this.

Because of its design and small size, the Toshiba reactor can't overheat or melt down, he said, unlike what happened in the 1986 accident at Chernobyl that killed 30 people and spewed radiation across northern Europe.

While the new type of reactor might be perfectly safe, why do they spread "disinformation" then? Of course, the "blow up" of Chernobyl only costed about 30 lives. The cleaning up recruits of the USSR army had about 1000 falacities later. Seems they don't count.

Anyway, besides the credibility of the press release the question of how to take care about burned out units remains.

How do you go about sinking something into the ground, that gets up to 500+ degrees C, without melting the permafrost? The Alaska pipeline has chilled pylons on it because the part above ground might get as warm as 75 degrees, thereby warming the part below ground enough to melt the permafrost.

I'll have to ask my uncle. He helped Bechtel build an oil refinery in northern Alberta...

The town is only about 700 odd people. One possibility is that if this gets near fielding, there will be a call by the anti-nuke groups for people to move there and basicly take over the town in order to stop it. There will also, of course, be lawsuit after lawsuit to delay it.

It's a must win for the antinuclear movement.

They'll view with alarm the small size, and especially the very low installation cost which makes it hard for long delays to bankrupt by increasing the cost of working capital.

That no plant has been ordered in the US for decades is a huge political point for them, and they'd see this as the camel getting a nose into the tent. I expect a bitter fight by them.

"Sure they say it's impossible to spill (radioactive material) for it to get out. But nothing in this world is impossible," he said.

Except, of course, for the public to rationally consider anything at all with "nuclear" in its name. That is really impossible.

What is it with people and "nuclear"? This reactor is suggested by the Japanese of all people. They were nuked. Twice. If anyone should automatically shut down his brain and cringe at the sound "nuclear", it should be them. Yet they seem to be thinking rationally about it. In the meanwhile, it is the Americans who nuked them who black out when hearing the word. What is this, some sort of guilt trip?

Wait, I got it. These Japanese are also scared of nuclear power. But they hell-bent on revenge! They'll install these miniature nuclear plants all over the USA, and at a predetermined time will cause them all to explode, killing everyone in the continent! Notice they don't suggest it be used in Japan? Launch a pre-emptive strike now!

It's called the Law of Mass Action, and it has nothing to do with politics or leaping out at anybody or talking funny or being a Luddite. It's a physical law that simply says that the more reactants you place in a vessel, the more product you're going to get. This applies to guns and it applies to nuclear waste. The more guns in circulation, the more people die. The more radioactive material in circulation, the more people get irradiated. You might as well pump cyanide gas into everybody's house and then pa

I did better than read about Hiroshima. I talked with a lady who lived there. She was born there and lived there her entire twenty-one years. That's right, Hiroshima is a thriving port city with about half a million people living in it.

Most of what messed up Western Europe was the hysteria whipped up by the media. Please show me the mass cases of sterility, mutation, birth defects, etc. rampaging across that continent right now.

The fact is, the radioactivity in the atmosphere of Western Europe matched tha

Chernobyl was caused by _engineers_ testing removal of cores, they took all the cores out and couldn't get them back in.

What will cause more fear is idiots like you under selling the risks.

Pot. Kettle. Black.

First, by cores, you mean control rods. But you're still somewhat off track.

Second, Chernobyl was an unstable, bad design, without a containment building. It's design, RMBK 1000, was such that if things went bad, the nuclear reaction would continue, instead of shutting down.

In addition to the uranium, a nuclear reactor needs two things- a moderator (which actually promotes the fission chain reaction) and a thermal transfer mechanism, to take heat away and make electricity with it. This is beyond the control rods, which are used to shut down the plant.

In every plant in the US, water acts as both the moderator, and the heat transfer mechanism. Lose the water, and the chain reaction is unsustainable. You can't take away heat anymore, but the fission chain reaction slows down dramatically. This is what happened at Three Mile Island (TMI)- they lost the water. They melted parts of their core, but that was the extent of the meltdown. The reactor vessel did it's job and physically contained the uranium. The containment building did it's job, along with all the auxillary systems, and no appreciable radiation was released to the public. TMI proved that we can handle a disaster without endangering the public.

Back to chernobyl. The RMBK 1000 reactor used water as a heat transfer mechanism, and graphite as a moderator. So when they lost water cooling, the reaction actually increased in power, and this raised power output lead to a rapid spike in temperature and pressure, blowing the lid off the reactor core and destroying the building.

Moreover, if they attempt to sustain low power levels (20% of capacity), the system is unstable. Because the core was huge, it was possible to have pockets of reactivity that couldn't be well controlled. When the power level is low, the cooling water/heat transport flow is reduced, to keep proper operating temperatures. But because they had pockets of reactivity that could be greater than average, there could be local areas where the flow was inadequate, boiling off the water prematurely, and getting us back the increasing reactivity with water loss that I mentioned earlier. Hence, they where supposed to operate below 20% power.

As for the people, despite earlier problems at different plants, they were not aware of the aforementioned technical problems. The Soviet bueacracy prevented any useful exchanges on such subjects. This is not to excuse them from not knowing more about their plant, just to paint a picture.

The cause of this was ironically a safety experiment. When a nuke plant is shut down, it still produces a significant amount of heat that must be removed. Normally the power required to run the pumps to remove this heat comes off the grid from other power plants, but if the plant is disconnected from the grid, a diesel generator is used instead. It took them three minutes to start the diesels (as opposed to a ten second standard in the US), so the engineers thought that they could bridge this three minute gap by extracting power from the turbine while it was in the process of coasting to a stop.

In order to test this theory, they deactivated every single safety system the plant had, and brought the power levels down to 6%. I've already talked about why this was bad.

At the end of their 'safety test', they inserted the control rods successfully, and in a hurry, because they could tell they were losing control of the plant. Because of the horrible design, though, these control rods where insufficient to kill the chain reaction, and instead only displaced water, which brought the power levels up to 100 times normal. Kaboom. The 'successful' insertion of the control rods was the final event in an idiotic string of actions.

Oh please, a nuclear reactor accident would be nothing like Hiroshima.

Do read about Hiroshima some time. Se how precisely the timing had to be constructed. Check the purity and mass and density specifications. Then try to construct a scenario in which a nuclear plant could even vaguly resemgle that.

Chernobyl is pretty much the worst that could happen, and there are plenty of safety precautions that could have prevented it.

In a worst case scenario with a nuclear powerplant, we're talking about, what, 50,000 years until it's safe again?

Nothing like that. Heck, people still live in Hiroshima and Nagasaki, which were subjected to far worse than what a nuclear powerplant would do. (Although it's possible that cancer incidence is still slightly higher there -- lots less than the equivalent risk from, say, smoking tobacco.)

Chernobyl was just about the worst case scenario for a nuclear plant -- and that was a really stupid design with a positive void coefficient and a graphite moderator -- which caught fire when the cooling water boiled away. Chernobyl still isn't the best place to hang out for very long, but there are other places that can be naturally more dangerous (such as downhill from a lake that occasionally bubbles toxic gases, such as the one that wiped out a village in Africa some years ago, or the valleys in geologically active regions that can collect lethal levels of sulfide gases and kill the occasional unwary hiker, and so on.)

Oh, and as for "Nuklear Power plant has a jet that flies into it.", in the US and Canada at least (and probably most other places), the result is a flattened jet and maybe a few scratches and scorch marks on the (many feet thick, reinforced, densified) concrete of the containment building.

It's been thought of. Google for "nuclear waste subduction". The problem is that subduction is a long, slow process, punctuated by violent activities like earthquakes and volcanoes.

You could accumulate a lot of waste in a given area that was slowly being pulled under, and then an volcano blows it all back up again. Or an earthquake cracks the seals and you've got contaminated groundwater or whatever.

The problems seem solvable with careful choice of site(s). There are places where the odds of such things are quite small. Pick someplace offshore, for one thing.

In reality, you'd have a greater risk of an accident in transporting the waste there than in any major incident happening.

Big article on this in Scientific American many years ago, in opposition to the Nevada waste site. Again the greatest danger is in transportation, but once entombed there is really no way for the material to harm anyone. You put a core dirlling ship in the ocean and dril a hole 2-3 kilometers into the ocean floor. You then drop barrels of waste into the hole separated by a few meters of the sediment. Even if the conatiners were to breach the material would at most disperse a few meters into the surrounding sediment over thousands of years. There is no worry of ground water contamination or even human contaimination once entombed, and eventually the material ends up melted into the mantle.

But, there is the threat of an accident during transportation, which is a worry for any nuclear waste disposal method.

Unless you (or your water source) lives in that desert, and said "corrosion-proof containers" have only been certified by "independent firms" hired by the waste control plant, there isn't much harm.

But my hometown lies 15 miles from Waste Control Services, and the plant sits right on top of the Ogalalla Aquifer from which the entire region pumps its water. The "corrosion proof containers" are metal barrels buried in a cement-lined pit. Along with the radioactive material are "non-corrosive" substances like old batteries and various forms of chemical, petroleum and medical waste. To top all this off, some "stabilized" napalm has been added to the mix as garnish.

Taken separately, these things are not harmful. Properly encased by well-trained robots in impervious material, these things are not harmful. But... packaged by overworked, underpaid, undereducated laborers in the cheapest material available with security checks run by firms hired out by the company to be yes-men, dumped together en masse in a cement pit, I'd say these things have the possibility for a big ka-boom.

Perfect logic. He's not talking about C02. He's talking about the gaseous uranium compounds released by burning coal. It's about six million tons a year if I remember right. That's six million tons of uranium, not C02.

He means that the amount of radioactive waste produced by a nuclear plant is less than the amount of radioactive waste produced by a coal-fired plant of equivalent power output.

And yes, coal is normally not considered radioactive. But it does contain traces of radioactive material, both in the coal itself and as waste rock from the mining process that isn't entirely separated. Not very much, of course -- but it takes thousands and thousands of tons of coal to produce the same power as a few pounds of uranium.

Of course, all radioactive waste eventually decays. We haven't even touched on the other stuff in coal ash that's highly toxic (like arsenic) that never decays.

I'll happily store the waste from the nuclear generated power I use in my backyard if you'll store the ash from the coal generated power you use in yours.

Have you visited a modern coal mining operation? I have personal experience with both. One hint that a modern coal mine is in the area is the fact that the river disappears. They rip the tops off of mountains and fill the valleys with the overburden. It's quite impressive until you think about what is happening to the surrounding environment. Moonscape doesn't begin to describe it.

As far as the heavy metal runoff from uranium mining, it is no worse than that at any other heavy metal mine. Or a gold mine for that matter.

Back feeding lines is an issue, but not as big as you might think. In nearly all cases your house is not the only one isolated, thus when you start backfeeding lines, all your neighbors think they have full grid power and start to use it, but since you don't have an unlimited supply of power, the breakers (and fuses) on your generators trip. Thus you are forced to correct the problem before you can use your own backup. That said, back feeding does happen, and it is dangerious. Dangerious enough that lin

Yeah, but SL-1 had control rods. With the control rods sticking all the time, the fault was found to be that the crew had to manually pull out a control rod to fix the control rod drive mechanism when it stuck. Well, some guy ended up pulling the control rod out too much, and the core went prompt critical (same thing that happened in the 1999 Japan accident when their mixture of uranium achieved critical mass). The coolant flashed to steam and shot the control rod out with the guy pinned to the ceiling. Because of SL-1, the navy changed all their reactor designs so that they could be shut down even with the most critical rod fully withdrawn, meaning that prompt criticality with one rod could never occur again. Obviously, Toshiba's reactor won't have the same problem since they're not even going to have control rods nor will they have any reactor coolant pumps. I'd be more worried about their new idea of using the reflector to control the power, not having any pumps, or using liquid sodium as the primary coolant.

The only commonality between the reactor you mention and the one in the article is that they are both nuclear reactors. The toshiba reactor uses a subcritical mass of uranium, so that it is inherently stable. A neutron reflector is used to cause a sustaining reaction. The reflector is sized specifically to create the temperature that the reactor is designed for (plus a margin in case you need to run a little hot) it is specifically designed not to be able to go supercritical and create a self sustaining reaction. There are no control rods because none are needed. Technology has advance alot in the last 4 decades. I wouldnt want to drive a car from 1961 either because they were also designed inherently unsafely.

"A small, 3MW experimental BWR called SL-1 (Stationary Low-Power Plant No. 1) in Idaho was destroyed on January 3, 1961, when a control rod was removed manually."snip"A careful examination of the remains of the core and the vessel concluded that the control rod was manually withdrawn by about 50cm (40cm would have been enough to make the reactor critical), largely increasing the reactivity. The resulting power surge caused the reactor power to reach 20,000MW in about.01 seconds, causing the plate-type fule to melt. The molten fuel interacted with the water in the vessel, producing an explosive formation of steam that caused the water above the core to rise with such force that when it hit the lid of the pressure vessel, the vessel itself rose 3m in the air before dropping back down (Derived from DOE and US Army records)"

1) 3MW not 200kW - Makes a difference2) It did "melt down" - effectivly anyway3) It did contain water (presurized or not I dunno)4) It was caused by human error5) It was probably a lot larger fuel block